RU2755646C1 - Device for setting, adjusting and forming the dynamic state of a vibrating technological machine and a method for its implementation - Google Patents

Abstract

FIELD: mechanical engineering.SUBSTANCE: device for setting, adjusting and forming the dynamic state of a vibrating technological machine contains a support surface, a compressor, a vibrator, and an elastic element. Lever elements are located on both sides of the desktop. The elastic-damping blocks are located in the case. The controlled chokes are controlled by two control units. The method reveals the creation and regulation of the device desktop with the vibration. The vibrations of the desktop are regulated by changing the pressure in the pneumatic cylinders and the rigid elastic-damping blocks connected to them. Information is obtained by means of vibration sensors.EFFECT: technical result is the possibility of adjusting the dynamic state of the vibrating technological machine by adjusting the parameters of the elastic lever structure.2 cl, 4 dwg

Description

The proposed invention relates to vibration technology and can be used to improve vibration technological machines for various purposes.

Vibration technologies, especially in recent years, have become widespread in the mining industries, chemical industries, the construction industry, metallurgy and mechanical engineering enterprises. Particular attention is paid to technologies and equipment for processing complex products in a vibrating working environment that provides shock and vibration interactions of granular and free-flowing mixtures with the surfaces of products. Vibration interactions of the working environment, interactions with the surfaces of parts, exhibit the effects of strengthening the mechanical properties and other effects of modifying the properties of surfaces, which ensures the reliability and durability of the parts in conditions of intense dynamic loading.

In many cases, the main unit in technological vibration complexes is a vibration stand that performs unidirectional vibrational movements of a harmonic form or more complex types, which is achieved by complicating and creating controlled means for exciting vibration fields.

The most widespread in the implementation of technological processes are vibration stands with one and two degrees of freedom, although in special cases more complex vibration stands are used that create spatial vibrations.

The issues of dynamic interactions of bulk media with vibrating surfaces are given serious attention, which was reflected in the works of A.P. Babichev, I.I.Blekhman, N.F. Goncharevich. and etc.; the peculiarities of taking into account the non-holding nature of the bonds in the contacts of the working medium with the surfaces of the working bodies of vibration technological machines were reflected in the works of domestic specialists [1 - 3].

The variety of tasks of vibration technologies initiated the development of appropriate technical means in the form of vibration stands, vibrating feeders, vibrating screens and other means, each of which predetermined certain possibilities for the formation of vibration fields of the working bodies of machines, as well as the implementation of certain modes of movement of working bodies, including conditions maintaining the stability of operating modes and adjusting them.

In many cases, vibratory technological machines, especially at the stages of its design, preliminary research, calculation, creation and operation, are considered as mechanical oscillatory systems with one or several degrees of freedom, in which the working body in the form of an extended solid body performs the corresponding movements (one at a time, two, three or more coordinates). The created vibrational technological complexes contain in their structure elastic and mass-inertial elements, dissipative devices, as well as mechanisms and devices that implement the functions of additional dynamic links.

Such dynamic connections ensure the integrity of the shaker structure, the possibility of setting, adjusting and forming dynamic states, including the ability to control the parameters of the technological complex in manual, semi- or automatic modes.

The possibilities of adapting the shaker to the conditions of technological regulations require appropriate approaches and taking into account the possibilities of expanding the functions of interaction with working environments or objects.

In this regard, it is of great interest to expand the capabilities of vibration machines in terms of the implementation of various modes of operation, which are achieved by the formation of the distribution of the vibration amplitudes of the points of the working body or the possibilities of forming the structure and features of the vibration field of the working bodies.

In this direction, there is a number of developments, which contain certain possibilities for expanding the functional set of vibration stands, focused on the implementation of technological processes of interaction of working granular media with processed products.

In the course of the patent search, a number of analogous inventions were identified.

The known method [Eliseev SV, Eliseev AV, Bolshakov RS, Vyong K.Ch., Mironov AS, Nikolaev AV. "Method for changing and adjusting the dynamic state of a vibration technological machine and a device for its implementation", 2710314, IPC V06V 1/14, priority 12/25/2019], including excitation of vibrations of the working body of a vibration technological machine and registration of displacements of the coordinates of movement of the vibration technological machine. According to the first invention, the vibration amplitudes of the extreme points of the vibration machine are recorded, the information received from the dynamic state control sensors is fed to the control unit, the ratio between these amplitudes is adjusted until a mode of their synchronous operation in two coordinates is obtained, and the ratio is adjusted by changing the reduced rigidity of the system. The device for implementing the method of adjusting and changing the dynamic state of a technological machine consists of a working body, elastic links pivotally attached to the working body and the supporting surface, as well as a control unit and sensors for monitoring the vibration state of the working body. According to the second invention, the device is provided with additional links in the form of two lever mechanisms, which contain pivotally connected rods in pairs, provided at the junction of the rods of each pair with a surcharge, and toothed sectors installed on the lower ends of the rods located at the bottom, while the toothed sectors are connected to the toothed blocks and brake pads interacting with the cylindrical surfaces of the gear blocks to influence the movement of the gear sectors.

The disadvantages of this invention are the complexity of the design and control system for the dynamic state of the vibration machine.

Known useful model [Violin D.O. "Vibration installation", 95574, IPC В22С 15/00, priority 10.07.2007], which is a vibration installation includes a frame mounted on a support, and a vibration exciter with an electric motor, characterized in that a metal block frame with a rubber a gasket along its edges, sheathed with steel thin-sheet rolled and made in the form of a parallelepiped, while the vibration exciter is made in the form of a working machine with a shaft having a changed center of gravity and mounted on sliding bearings, and the shaft of the working machine and the electric motor are interconnected by a coupling and rigidly fixed through the supports to the iron plate through the rubber gasket to the frame frame.

Disadvantages of the presented analogue: the lack of a mathematical description of the operation of the vibration machine and the means for regulating the dynamic state.

A vibration machine is taken as a prototype [Rumyantsev YS, Ananin IK, Galyapin DV, Konyukhova MN. "Vibration machine", 153829, IPC В24В 31/06, priority 08/10/2015], containing a base in the form of a lower frame on which an electric motor of the unbalance drive is mounted, stands for fastening intermediate bearing supports and elastic supports in the form of pneumatic bellows, and an upper movable frame , designed for the installation of containers for workpieces, on which the unbalance shafts are mounted, connected to the drive shafts through flexible couplings, while the upper movable frame is connected to the lower frame through elastic pneumatic supports, the struts of which are connected to the pneumatic system containing shock absorbers, characterized in that the pneumatic system is branched into two independent lines of the same composition, each of which includes a pressure switch, a pneumatic valve and a level regulator of the upper movable frame, containing a lever, each of which includes a series-connected level regulator of the upper movable frame, while the levers of the said level adjusters are connected to the upper movable frame, each on its side, and regulator inputs are connected to mon the euro system.

The main disadvantages of the prototype include the lack of a detailed mathematical description of the operation of the vibration machine and attention to the rotational component of the movement.

The objective of the present invention is to adjust the dynamic state of the vibrating technological machine by adjusting the parameters of the elastic-lever structure.

A device for adjusting, correcting and forming the dynamic state of a vibration technological machine, including a support surface, a compressor, a vibrator, a work table, an elastic element, characterized in that lever elements are additionally introduced on both sides of the work table, elastic damping blocks located in the housing containing two blocks controls, with the help of which controlled chokes are regulated.

A method for setting, correcting, forming and controlling the dynamic state of a vibration technological machine, including the creation and regulation of the vibration of the working table according to claim 1, characterized in that the vibrations of the working table are regulated by changing the pressure in the pneumatic bellows and the rigid elastic-damping blocks connected to them according to the information, obtained with the help of vibration sensors.

The essence of the invention is illustrated by drawings.

FIG. 1 shows a schematic diagram of a vibrating technological machine with additional connections in the implementation of specific modes, containing a support surface 1, rigid rods 2, 17, 18, 23, guide rods 3, 16, elastic-cord elements 5, 15, controlled throttles 6, 7, 10, 11, 12, damping pneumatic blocks 8, 9, pneumatic compressor 13, elastic elements 19, 24, vibration sensors 20, 22, working body 21, information processing and control units 4, 14.

FIG. 2 shows a design diagram of a technological vibration machine, a schematic diagram of which is shown in FIG. 1.

FIG. 3 shows a structural mathematical model (block diagram) of the original mechanical oscillatory system according to FIG. 2.

FIG. 4 shows the Possible variants of the distribution forms of the ratio of the vibration amplitudes of the points of the working body (the structure of the vibration fields).

The invention works as follows.

и

и создающие внутренний настроечный контур, получаемый соединением через направляющие стержни 3, 16 с системой пневмоблоков, которые состоят из упруго-кордных элементов 5 и 15, связанных с демпфирующими (жесткими) пневмоблоками 8, 9, создающими жесткую опору для деформационных движений этих элементов по горизонтальным направлениям. Образованное последовательными соединениями пневмоблоков структурное образование обладает возможностями формирования приведенных жесткостных свойств при использовании дросселей 6, 7, 10, 11, 12. Компрессор 13 через систему дросселей обеспечивает необходимый уровень давления в пневмоблоках и, тем самым, и их упругие характеристики.The proposed invention is carried out by a mechanical oscillating system, consisting of a working body in the form of an extended solid body 16, having a mass M and a moment of inertia J, resting on elastic elements (spring) 19, 24 contacting with the support surface 1. Parallel to the elastic elements 19, 24 introduced additional linkage, consisting of rigid rods 2, 17, 18, 23 with lengths

and

and creating an internal tuning contour obtained by connecting through the guide rods 3, 16 with a system of pneumatic blocks, which consist of elastic-cord elements 5 and 15 connected with damping (rigid) pneumatic blocks 8, 9, creating a rigid support for the deformation movements of these elements along the horizontal directions. The structural formation formed by serial connections of pneumatic blocks has the ability to form the reduced stiffness properties when using throttles 6, 7, 10, 11, 12. Compressor 13 through a system of throttles provides the required pressure level in the pneumatic blocks and, thereby, their elastic characteristics.

To ensure the interaction of the elements of the system, the position of which is monitored by the sensors 20, 22, the transfer of information to the control units 4, 14 through the corresponding communication is provided. Through the control units 4, 14, the operation of the petal-type chokes is also regulated, which allows in manual mode, using the readings of the sensors, to reach the desired operating modes. If necessary, such work can be implemented on the basis of a microprocessor. The peculiarity of the proposed approach lies in the use of the features of the dynamic interaction of the elements of the system, its dynamic connections, which allow the formation of the necessary effects of coupling of vibrations along the coordinates y ₁ , y ₂ in certain frequency ranges, which is achieved through varying the dynamic stiffness created by controlled pneumatic blocks within a simple system on the basis of the compressor.

Theoretical justification

The schematic diagram of a vibrating technological machine (Fig. 1) can be interpreted by a mechanical vibrating system with two degrees of freedom, as shown in Fig. 2. It is assumed that a rigid body with mass M and moment of inertia J, resting on springs with stiffness k ₁ and k ₂ , reflects the properties of the working body. The system possesses linear properties of all constituent elements and performs small oscillations relative to the position of static equilibrium. Movement system considered in the coordinates y _1, y ₂ and y _0, φ, where ₁ - is the offset of the point A _1, y ₂ - V ₁ point offset, y ₀ - displacement of the center of mass located at t O;. ϕ is the angle of rotation of the rigid body (M, J) relative to the horizontal.

и

от тт. А₁, В₁ соответственно. Внешнее воздействие, создающие колебания рабочего органа (твердого тела М, J) приложено в т. Е на расстоянии

от центра масс (т. О). Точки А₁ и А₀, также как тт. В₁, В₀ соединены двухстержневыми структурами рычажного типа с длинами

для обеспечения движение тт. А и В, которые связаны с работой упругих элементов с приведенными коэффициентами жесткости, k_pr1, k_pr2. Прижимы одним концом связаны с тт. А и В соответственно, а другие - упираются в вертикально стоящие ограничитель. Расчетная схема носит условный характер, что создает возможности аналитических расчетов; более сложная интерпретация системы приводится на фиг. 1. Приведенные жесткости упругих элементов k_pr1, k_pr2 отображаются достаточно сложные взаимодействие пневмоблоков, упругих и диссипативных типов, что, в существенной мере, зависит от параметров дросселей, соединяющих пневмоблоки, объемов устройств и давления воздуха, создаваемого специальным компрессором. При выводе уравнения движения используется упрощенный подход.The center of mass (point O, Fig. 1) is located at a distance

and

from vols. A ₁ , B _1, respectively. External influence creating vibrations of the working body (solid M, J) is applied at point E at a distance

from the center of mass (m. O). Points A ₁ and A ₀ , as well as vols. B ₁ , B _{0 are} connected by double-rod structures of lever type with lengths

to ensure the movement of vols. A and B, which are associated with the work of elastic elements with reduced stiffness coefficients, k _pr1 , k _pr2 . The clamps are connected at one end with vt. A and B, respectively, while others rest against a vertically standing limiter. The design scheme is conditional, which creates the possibility of analytical calculations; a more complex interpretation of the system is shown in FIG. 1. The reduced stiffness of the elastic elements k _pr1 , k _pr2 shows a rather complex interaction of pneumatic blocks, elastic and dissipative types, which, to a significant extent, depends on the parameters of the throttles connecting the pneumatic blocks, the volume of devices and the air pressure created by a special compressor. A simplified approach is used to derive the equation of motion.

To derive the differential equations of the system in the time domain for the circuit of FIG. 2 uses the Lagrange formalism [4].

Let us write expressions for kinetic and potential energy, which will be

The calculations use the following ratios:

I. The system of differential equations of motion in coordinates y ₁ , y ₂ takes the form:

The resulting system of equations (4), (5) can be represented in operator form after integral Laplace transforms with zero initial conditions [4]:

значок «-» над переменной означает ее изображение по Лапласу [4].where p = jω is a complex variable

the “-” sign above a variable means its Laplace image [4].

On the basis of differential equations (6), (7) in operator form, a structural mathematical model of the original system shown in Fig. 2.

The structural mathematical model is a structural diagram of a dynamically equivalent automatic control system. The structural model is shown in FIG. 3 and consists of two partial blocks, interconnected by a link reflecting mass-inertial dynamic links, characteristic of mechanical vibrational systems containing rigid bodies that perform plane vibrations, as the sum of translational vertical and angular vibrational motions.

II. The structural mathematical model makes it possible to obtain the transfer functions of the system. The physical meaning of these concepts is associated with the assessment of the dynamic compliance of the displacement of coordinates from the frequency of the disturbance when it is applied at a given point at a certain frequency. A graphical representation of this relationship is called the system's frequency response (AFC); analytical expressions for the transfer functions of the system are:

where

- is the frequency response equation.

It follows from equation (10) that the system has two natural frequencies. In addition to natural frequencies, partial frequencies are taken into account, which is, according to the first block:

for the second partial block:

The value of partial frequencies can be used in assessing the dynamic properties of systems and the possibilities of using it in the formation of dynamic states of the working body.

и

формируются под одновременным действием двух силовых факторов

и

приложенных на входах первого и второго парциальных блоков, соответственно, как показано на структурной схеме (фиг. 3).III. In assessing dynamic states, the values of the frequencies of dynamic damping of oscillations are also essential. The specificity of the invention lies in the fact that the dynamic state of the system in coordinates

and

are formed under the simultaneous action of two force factors

and

applied at the inputs of the first and second partial blocks, respectively, as shown in the block diagram (Fig. 3).

The values of the frequencies of dynamic vibration damping are determined by the expressions:

или

связано с возникновением так называемых узлов колебаний или локальных центров вращения рабочего органа относительно центра вращения. Если, например,

то твердое тело на частоте динамического гашения будет совершать угловые колебания относительно т.

тогда амплитуда колебаний точек твердого тела примет линейное распределение, поскольку

Аналогичная ситуация возникает при динамическом гашении колебаний по координате

когда

The effects of dynamic damping in the analysis of the dynamic states of the working body of the system are of particular importance, since the "zeroing" of the coordinates

or

associated with the emergence of the so-called vibration nodes or local centers of rotation of the working body relative to the center of rotation. If, for example,

then the rigid body at the frequency of dynamic damping will perform angular oscillations relative to m.

then the vibration amplitude of the points of the rigid body takes on a linear distribution, since

A similar situation arises with dynamic damping of oscillations along the coordinate

when

IV. The authors of the invention propose an original approach for a generalized assessment of the possibilities of manifestation of dynamic states of other types, which expands the understanding of the possibilities of constructing the structure of vibration fields and its adaptation to the regulations of the technological process.

; в дальнейших расчетах принимается, чтоThe concept of the transfer function is introduced not for the system, but for the transfer function of interpartial connections. The concept introduced reflects the features of the formation of dynamic linkages created by vibrations of the working body and estimated by the ratio

; in further calculations it is assumed that

The transfer function of interpartial connections also has an amplitude-frequency characteristic, but its physical content will be different in comparison with the frequency response of the system.

In the case under consideration, the transfer function of interpartial connections has the form:

The resulting expression (15) takes into account the forms and features of the interaction of the elements of the design scheme (Fig. 2), which reflects only the main properties of the original technical object, which includes a number of structural formations built on the use of a system of pneumatic blocks, which can be combined with a corresponding set of involved adjustable throttles ; at the same time, the system has the ability to regulate the pressure in the pneumatic blocks, which, in general, creates a sufficiently large potential for solutions that can be used to build rational technological solutions.

).Below we consider the technology of constructing mathematical models that reflect the possibilities of choosing a strategy and tactics for managing dynamic states displayed by the transfer functions of interpartial relations (or coefficients of connectivity of motion along coordinates

).

Specific modes of dynamic states.

1. If, when using expression (16), the mode is investigated when W ₁₂ (p) = 1, then it is possible to find the oscillation frequency at which such a mode is realized. In this case:

then

At the frequency ω _I determined from (18), the working body will perform translational vertical oscillations; in this case, the angular vibrations are "zeroed". If this effect is explained using the concept of the center of vibrations, then it can be argued that such a point is outside the working body on the continuation of the working body line parallel to the supporting surface).

2. For the case W ₁₂ (p) = - 1, expressions (16) are used, we can obtain that:

In the case of W ₁₂ (p) = - 1, the vibration center is located in the middle of the working body (solid); in this case, only angular vibrations are performed (there are no vertical translational vibrations). The ratio of the oscillation amplitudes of the points of a rigid body reflects that feature of the movement of the working body, which consists only in symmetric angular oscillations relative to the center of oscillations in the absence of vertical oscillatory movements.

3. By changing the parameters (we mean the mass-inertial parameters of the system M, J; elastic properties k ₁ , k _pr1 , k ₂ , k _pr2 or the parameters determined by the values a, b, c, c ₁ , it is possible to change the position of the vibration center by solid.

будет изменяться, то взять за исходную позицию положение центра колебаний при

можно отменить, что принимая

значения -0.9; -0,8…-0.1; -0.001 центр колебаний будет смещаться и совпадет с т. А, когда возникнет режим динамического гашения колебаний по координате

If the ratio of vibration amplitudes

will change, then take the position of the vibration center as the initial position at

you can cancel that taking

values -0.9; -0.8 ... -0.1; -0.001 the center of vibrations will shift and coincide with point A, when a mode of dynamic damping of vibrations occurs along the coordinate

предельным случаем будет совпадение центра колебаний с точкой В₁, когда по координате

реализуется режим динамического гашения.When moving to the right of the position,

the limiting case will be the coincidence of the center of vibrations with point B ₁ , when the coordinate

the dynamic blanking mode is realized.

4. When choosing ratios within:

или

может интерпретироваться как вращательное движение.The center of vibrations will be outside the working body; this will be a point lying on the extension of the line of the surface of the working body, parallel to the supporting surface. The movement of the working body, determined by coordinates

or

can be interpreted as rotational movement.

FIG. 4 shows variants of possible variants of the distribution forms of the ratio of the vibration amplitudes of the points of the working body, depending on the location of the vibration centers.

The above shows the possible options for influencing the distribution of the parameters of oscillatory systems, which can be achieved by introducing additional dynamic links, created by elastic elements with adjustable parameters, into the design diagrams of vibration technological machines; in this case, elastic elements based on pneumatic blocks connected to each other through controlled throttles with the ability to change the rigidity parameters of the system as a whole when the pressure in the pneumatic blocks changes with the help of a compressor. The formation of dynamic states can be provided by the simplest means of changing the vibration parameters of two points of the working body and the simplest calculation algorithm.

The proposed approaches can be implemented in the manual setting mode.

Used Books.

1. Kopylov Yu.R. Dynamics of vibroimpact hardening processes: monograph / Voronezh: IPC "Scientific book", 2011. - 569 p.

2. Panovko G.Ya. Lectures on the basics of the theory of vibration machines and technologies. M .: MGTU im. Bauman, 2008 .-- 192 p.

3. Weisberg L.A. Vibrating screening of bulk materials. Modeling of processes and technological calculation of screens / L.A. Weisberg, L.G. Rubisov // Mechanobr. SPB. 1994 .-- 45 p.

4. Eliseev S.V. Applied system analysis and structural mathematical modeling (dynamics of transport and technological machines: connectivity of movements, vibrational interactions, linkages): monograph - Irkutsk: IrGUPS, 2018 .-- 692 p.

Claims (2)

1. A device for setting, correcting and forming the dynamic state of a vibration technological machine, including a supporting surface, a compressor, a vibrator, a work table, an elastic element, characterized in that lever elements are additionally introduced on both sides of the work table, elastic damping blocks located in the housing, containing two control units by means of which the controlled throttles are regulated. 2. A method for setting, correcting, forming and controlling the dynamic state of a vibrating technological machine by the device according to claim 1, including creating and regulating the vibration of the working table, characterized in that the vibrations of the working table are regulated by changing the pressure in the pneumatic bellows and the rigid elastic damping blocks connected to them according to information obtained using vibration sensors.

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